English to Italian Tech/Engineering Nuclear Eng/Sci

Indoor reel system
Inside the towers a hose reels for each floor and wall is supplied.
Hose reels installed along of all coal belt conveyors, for each side (right and left of stairways belts.)
The distance from the reels located along of belt conveyors is not more than 40 m for each side.
Hose reel position is sized in order to assure that each point of the protection area can be reached from two Hydrants.

il documento in questione descrive la progettazione e la realizzazione di una centrale per la manipolazione del carbone dotata di cupole (Domes).
stairways belts indica qualcosa di tecnicamente più specifico o si può tradurre letteralmente?

grazie in anticipo